Adds attach example

Cargo.toml

@@ -20,6 +20,9 @@ bitflags = "1.0"
 version = "0.4"
 path = "./lxc-sys"
 
+[dev-dependencies]
+libc = "0.2"
+
 [features]
 v1_0 = []
 v1_1 = ["v1_0"]

examples/attach.rs

@@ -0,0 +1,53 @@
+use std::os::unix::io::AsRawFd;
+
+fn main() -> std::io::Result<()> {
+    let c =
+        lxc::Container::new("apicontainer", None).expect("Failed to setup lxc_container struct");
+
+    if c.is_defined() {
+        panic!("Container already exists");
+    }
+
+    c.create(
+        "download",
+        None,
+        None,
+        ::lxc::CreateFlags::QUIET,
+        &["-d", "alpine", "-r", "3.14", "-a", "amd64"],
+    )
+    .expect("Failed to create container rootfs");
+
+    c.start(false, &[]).expect("Failed to start the container");
+
+    let mut options = lxc::attach::Options {
+        stdout_fd: std::io::stdout().as_raw_fd(),
+        stderr_fd: std::io::stderr().as_raw_fd(),
+        stdin_fd: std::io::stdin().as_raw_fd(),
+
+        ..lxc::attach::Options::default()
+    };
+
+    let r = c.attach(
+        Some(lxc::attach::run_shell),
+        std::ptr::null_mut() as *mut std::ffi::c_void,
+        &mut options,
+    );
+
+    match r {
+        Ok(pid) => wait(pid),
+        Err(e) => println!("{:?}", e),
+    }
+
+    c.stop().expect("Failed to kill the container.");
+    c.destroy().expect("Failed to destroy the container.");
+
+    Ok(())
+}
+
+fn wait(pid: i32) {
+    let mut status = 0;
+
+    unsafe {
+        libc::waitpid(pid, &mut status, 0);
+    }
+}